This section provides background information related to the present disclosure which is not necessarily prior art.
Joint replacement prostheses commonly comprise two bone engaging components that articulate via a bearing component. In a total knee replacement prosthesis, the bone engaging components are a femoral component, comprising an anterior surface with patella track and two femoral condyles, and a tibial component, comprising a substantially planar surface or tray and a post, keel or other stabilising feature. The femoral and tibial components articulate via a bearing component mounted on the tray of the tibial component. The bearing component may be fully or partially fixed with respect to the tibial component, and commonly comprises a single piece of high density polyethylene.
In order to more closely replicate the natural kinematics of the knee, it is desirable for a total knee replacement prosthesis to facilitate a combination of rolling, rotational and translational movement between the femoral and tibial components of the prosthesis. This can be achieved in part by employing a “mobile” bearing component, having some freedom of movement relative to the tibial component on which it is supported.